Peterson&Peterson - duration in STM

• pts were shown a trigram e.g CPW that mean nothing. then pts had to count backwards in 3s from a specified 3 digit number.
• After intervals of 3,6,9,12,15 or 18 seconds, the pts were asked to recall the original trigram
• this was repeated several times for each person using different trigrams (repeated measures)
• after 3 seconds, average recall was about 80%
• After 18 seconds recall was about 3%
• as relational interval increased, percentage of accurate recall of trigram decreased (NOT a correlation)
• P&P concluded info disappears (decays) very rapidly from STM when rehearsal is prevented